Upgrade to SnakeYAML 1.16

Closes spring-projectsgh-3879

Author: wilkinsona

spring-boot-dependencies/pom.xml

@@ -122,7 +122,7 @@
 		<servlet-api.version>3.1.0</servlet-api.version>
 		<simple-json.version>1.1.1</simple-json.version>
 		<slf4j.version>1.7.12</slf4j.version>
-		<snakeyaml.version>1.15</snakeyaml.version>
+		<snakeyaml.version>1.16</snakeyaml.version>
 		<solr.version>4.10.4</solr.version>
 		<spock.version>1.0-groovy-2.4</spock.version>
 		<spring.version>4.2.1.RELEASE</spring.version>